Interactions between herbal and conventional drugs have reported in more than 100 cases. One study has considered warfarin as the most common drug, and St. John’s wort as the most common herb implicated in interactions. Other herbs included Ginseng, Garlic and Kava. For example, patients can experience bleeding, bruising and headache if they use ginkgo and antiplatelet or anticoagulants concurrently. Also pharmacokinetic interactions with St. John’s wort leading to a loss of or reduction in the therapeutic activity of the medicines such as: anticonvulsans, digoxin and theophylline. In this article We reviewed some Case report interactions between herbs and drugs. Also interactions between 35 herbs with conventional drugs were presented in tables.